Film guiding and positioning means



April 17, 1956 c. c. RIVAS FILM GUIDING AND POSITIONING MEANS OriginalFiled Dec. 18, 1950 INVENTOR. 6421.03 6. 2/1/45 I: i 1 'ztorvzgy iapplicati apart the resilient means.

- mazes; enema it-Ni resiuosise cause Rivas; Htiil'ywdoki; @aiiftassess; ta Manw serraneg Angel-es; cane D e ba i 1.131 1 S ial iq- G1,43.now Patent serial Nas zat 0 p r 4 Claims: oi. an -4.3

This invention alas t a paratus for etting. a tape,

r filth and a sle part-r n a devieepera ittia a film to be readilyplaced in engagement with afro tatable git'iidiiially anteain either}direction withautpe aaiing separ ted near the means e ement throughunintennenst transverse or veitiea mat/smear er he film. I v

This appu'c'atien is a division at my c pendi g, apple cation Serial No.Z OlASQ fiIYed December 1 8, l9 51l, for Magnetic s ouiid Record EditiiigMacliinefnow Patent Nags-47,155, (rate uly 2 1953.

is t6 be co'n'side'rdas meant-fi any type er auna-recordiiig tape orwire, or any type of film such as motion-picture filin for example.

vaueus me ian-8m are presently em loyed re uisi iihg a film inengagement with a dri ving or supp orting riiar'is as a rotatingsprocket wheeh These systems sult in tearing ofthe-film if for example,the sprocket teih iii the s tting whel we're' not properlyaligned withare specter notes in the film. a

It is a primary object of the present invention to provide an improvedfilm guiding and positioning mechanism which readily permits a film tobepropcrly threaded on a sprocket whee operatien. a V g Vltnotherfobject is to provide subhf film g'a'fing niel'ianisin whichwill not result-in th tearing or are aging of a film should the sprocketholes therein not register properly with the sprocket teeth on theWheel.

Another object is to provide a film holding mechanism in which a filmcan be readily inserted or removed with substantially less possibilityof damaging the film.

These and further objects of the present invention are attained byproviding on opposite sides of a driving or supporting rotatableelement, resilient means adapted to overlie the peripheral edges of theelement throughout an arcuate portion of its circumference. Theseresilient means are adapted to slide apart or together in a directionparallel to the axis of the rotatable element, the film itself acting asthe spreading means when it is inserted or removed. This action ispermitted by virtue of the arcuate shape of the resilient meansrendering the portion of the film lying over the rotatable elementtransversely rigid wherebyit is sufficiently strong to wedge Thus,threading of the film liable sprocket wheels; must a a awa e in se thpositive efigigir'ig feature at these clamps 'could often re-} usuallyincorporate leventype cram s" which may be" Y 2,742,283 a a n ed A :1 56

. as Ln n s mp Ru hing t ntg nsasem nt ththe ro t b element. Si rn ilarlin remoying thefilmit isonly necessary to litt itoif he rotatableelement. 7

A Be i er d ne at hnn em oawi i i h ai y f i i i 5 q f nq s eta d ssfipon in coniuncev a w t as mp nxia draw n sli we avatar Flgure 2 claws,

f r in a ta ts-r. esi wiiih use. i

a frame or, support ltl which may bepart ,ofa irrqn 11-;

a q vj P aet im r t eq t n 'i m d a machine tor example, supportingadriving unit; generally designated by thenumeral 11. A rotat'ableelement in the form of: a sprocket wne'ei i2 keyed toa shaft13isj- 23areiresiliently positiondinthe cavities by coil springs 25 fitted insuitable bores formed in the claws 22 and;

bearing against the end walls of th e cavities 25% in the arms 21 ,Withthis arrangement the claws 22 overlie e r f ne the ma Wh el 2w matpushed back into their respective cavities by a-spreading force.

opposite sides of each clan? and eugag dgby flanges 27 on angular clips-28. The other ends of clips v 28 are eci i dtin s t blats es s 2.9 vteta mswzt kel The clip niayb'e rem ovcdby slidingthem upwardly,athis',ass

tio releasing the-claws 22 a1-1d permitting them to be" removed from thecavities 24. r g r n j a One of the claws 22 is shown in perspective inFigure 4. Singe these claws ajre identical descriptioneof one willsuflic for both t As shown in Eigure"4;, the claw has rounded ed ges 40,4I;;.androundedcorners .42: The

arcuate'bearing; surface 23 isvadaptedto covert about 60degreesotthe-sprocket wlaeel-12; The film 14 is; th'ere fore; bentsubstantially degrees when passing over the sprocket Because; 9i: this.l20 .degrez'berrd in;the

filin sufiigient lateralgtstiifness jis deyelopediri ,thje bentliportion to prevent any possible transverse buckling of the film such aswould be necessary in order for the film to escape from the opposedclaws 22 engaging the opposite film edges.

The whole driving unit, including the yoke 20, is disposed such that itslongitudinal axis will bisect the angle between the operative stretch offilm 14; that is, between the respective portions thereof which extenddownwardly to the left into a suitable receptacle (not shown) from whichthe film is being withdrawn, and upwardly to the right'to the mechanisminto which the film is being fed. This angle of the yoke and drivingunit may conveniently be adjusted by means of the tightening bolt 15slidably operable in the slot 16 in the frame 10. With the angle of thedriving unit and the yoke 20 properly adjusted, the arcuate bearingsurface 23 of the claws 22 will be tangent to the film at all pointsthroughout the are.

In applying the film 14 to the driving unit 11 the film igure l showsa,side;-view of a preferred F'gure 4 is a perspective view of iieltt theear ng to Figurfe 5,; (its transverse wa of as claws; 22 is limited bymeans ofnotches 26 formed in eration is performed practicallyinstantaneously, it being possible for the operator in one quickmovement to grasp the film and force it downwardly between claws 22 inone continuous motion, the claws snapping apart and back together againso as to secure the arched portion of the film in the passes formedbetween the periphery of thesprocket wheel and the-corresp'ondingarcuate bearing surfaces 23 of the claws 22. In removing the film areverse procedure is followed. The operator grasps the incoming oroutgoing portion of the film and simply pulls upwardly causing therespective edges of such portions to arch upwardly at the extremities ofclaws 22 and to exert upward pressure against the rounded corners 42.Such upward pressure is translated into spreading pressure which forcesthe claws 22 apart and allows the tape to become free therefrom.

It will be seen that'this hold-down arrangement saves considerable time,which, in existing machines where any tape or film is fed betweensprockets is wasted to a considerable extent in threading the tape orfilm across the sprockets and beneath suitable holding devices. Also,the

present apparatus is not likely to break or tear the film It is also tobe noted that because of the resilient nature of the claws 22, shouldany of the perforations not when it is being inserted into or removedfrom the driving unit. a

properly register with the sprocket teeth, the resulting upward movementof the tape or film will be accommodated by the automatic retraction ofclaws 22 due to the spreading action of the film. If a positiveholding-down clamp means were used the sprocket teeth would simply tearnew holes in the film.

While a specific type of resilient claw is illustrated, it is to beunderstood that any resilient means having rounded bearing surfaces maybe utilized. The invention, therefore, is not tobethought of as limitedto the precise embodiment disclosed.

I claim:

1. An apparatus for guiding film comprising in combination: a-rotatableelement for engaging a film, a support member-extending upwardly on oneside of said rotatable element, another support memberextending upwardlyon the opposite side of said rotatable element, said members definingopposing cavities, claw members resiliently mounted in said cavities andadapted to overlie op posite peripheral edges of said rotatable element,said claw members having roundedcorners whereby insertion of a filmbetween said support members into engagement with said'rotatable elementwill momentarily retract said claw members into said cavities.

2. An apparatus for guiding film comprising in combination: a rotatableelement for engaging a film, a pair of spaced arms embracing saidrotatable element and having end portions projecting beyond theperiphery of said element, and a pair of spaced claws mounted in saidend portions respectively, for limited spreading movement parallel tothe axis of said rotatable element, said claws having bearing surfacesspaced from the periphery of said rotatable element to define passesslightly wider than the thickness of said film andoverhanging saidperiphery so as to confine the edges of a portion of film resting onsaid periphery, saidbearing surfaces being contoured to said peripheryso as to maintain said portion of the film stretched in the form of asegment of a cylinder,

' whereby to impart transverse stiffness thereto for maintaining thefilm engaged in said passes, said claws having extremities definingrounded corners, which when a stretch of film under tension is pressedthereagainst, may react to the wedging action to spread said claws apartso as to permit entry or removal of the film from said passes inresponse to pressure exerted by the film either toward or away from saidrotatable element.

3. An apparatus or guiding film, comprising: rigid, generally U-shapedsupporting means forming a pair of spaced, rigid support members adaptedto receive a gentance inwardly of the inner opposed edges of saidsupport members whereby said inner ends are adapted to overlie oppositeperipheral edges of said element, said claw members being movable awayfrom each other to retracted positions to accommodate passage of a filmtherebetween, said claw members having rounded corners to facilitatesaid passage of the film, and means resiliently biasing said clawmembers to their extended positions. v

' 4. The subject matter of claim 3 including means releasably securingsaid claw members to their respective support members.

References Cited in the file of this patent UNITED STATES PATENTS2,549,271 Weinke Apr. 17, 1951

